"Any opening up doesn't happen overnight," he said. "I think it will be more like years than days" before end-users notice the effects, he said.

Ray Ozzie, Microsoft's chief software architect, added that it was hard to predict what kinds of new products might become available to users because of this change. "One thing the Net has shown is that sometimes, constraints around standards can be quite liberating to developers," said Ozzie.

"Many times, new services pop out of nowhere once a standard is there and once interoperability principles are established, because we can't think of the different potential uses of customer data and how to interface with products."

Phil Dawson, research vice president at analyst Gartner, said, “This is a great step forward and other vendors will have to consider what they do.” So too will CIOs and IT directors, he added.

Dawson agreed with Ballmer that end user organisations would probably have to wait two or three years to get the benefits of Microsoft’s move. But he urged them to start preparing for the impact of the move. It will, he said, “help decouple proprietary standards in the data centre and this will give savings.” As a result, “integration and services will be easier,” he added.

Dawson warned CIOs and IT directors to bring their IT architecture teams into the discussion of the impact of Microsoft’s announcement right away. “Don’t keep this in the infrastructure and operations group; get it to the guys who are closer to the business.” The result will be easier integration and better services, he added.

Janice McGinn, The 451 Group's research director, CIO Practice, said many said many senior IT leaders would react to Microsoft’s announcement with cynicism, but others could be tempted to consider open source products.

She noted, “Many who are wary of using open source in anger at the enterprise level and the consequent risk to brand – real or perceived – will be more likely to take Redmond’s route to open,” as a result of the announcement.